A bearing arrangement according to the class with a backup bearing is known from DE 10 2011 005 761 A1. The backup bearing represents a safety device that allows, in the event of the failure of a magnetic bearing, the danger-free running down of a shaft supported by magnets in ordinary operation. For this purpose, a housing holding the backup bearing has a slot that extends essentially in the circumferential direction of an outer ring of the backup bearing and is formed as a through hole. The slot extends, for example, over a circumferential angle from 50° to 180° and has a width of less than 2 mm. If a magnetic bearing provided for supporting the shaft fails, the shaft is supported by the backup bearing, wherein the walls of the slot providing a spring path can form a block.
Another backup bearing for a magnetic bearing is known from DE 10 2010 035 183 A1. An outer ring of this backup bearing is surrounded by a damping ring that has recesses arranged at regular positions on its lateral surface. Such a backup bearing is provided, for example, for use in electrical machines or turbochargers.
DE 10 2010 032 111 A1 discloses a backup bearing for a contactless, supported rotor in which two outer ring parts are clamped elastically relative to each other in the axial direction. Both outer ring parts contact a centering ring that has the task of centering the outer ring parts in the radial direction with a positive fit connection to each other, in particular, when the outer ring parts are pressed away from each other in the axial direction due to a radial force acting on the backup bearing.
To damp a bearing ring, in addition to mechanical damping elements, hydraulic damping devices are also basically known. One example here is disclosed in patent DE 10 2006 026 123 B4 that relates to a method for damping movements of a rotor in the radial direction relative to the rotor axis. A ring gap running about the rotor axis is here filled with a viscous medium that is loaded as a function of the operating state of the rotor with different pressures.